Attorney Russ Oliver says he issued a subpoena to appear for a deposition because he thinks Nixon has knowledge about the case. He expects the subpoena to be delivered Tuesday. It orders Nixon to appear on May 3.

A Nixon spokesman had no immediate comment.

Oliver is representing Eric Griffin, of Advance, in a lawsuit challenging new requirements for license clerks to scan personal documents, such as birth certificates and concealed weapons endorsements.

A judge in the case already denied an injunction request to force the department to stop scanning documents.

Nixon announced earlier this month that weapons endorsements would no longer be scanned.

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